Affiliation: | 1. Oxford University Centre for Business Taxation, Park End street, Oxford OX1 1HP, UK (e‐mail: giorgia.maffini@sbs.ox.ac.uk);2. Office of Gas and Electricity Markets (OFGEM), 9 Millbank, London SW1P 3GE, UK (e‐mail: Socrates.Mokkas@ofgem.gov.uk) |